[U-Boot] [PATCH v2 13/15] env: Mark env_get_location as weak

[Simon Glass]

Hi,

On 22 January 2018 at 09:36, Tom Rini <trini at konsulko.com> wrote:
> On Mon, Jan 22, 2018 at 04:57:41PM +0100, Maxime Ripard wrote:
>> On Mon, Jan 22, 2018 at 07:49:41AM -0500, Tom Rini wrote:
>> > On Mon, Jan 22, 2018 at 01:46:46PM +0100, Maxime Ripard wrote:
>> > > Hi,
>> > >
>> > > On Sun, Jan 21, 2018 at 05:29:56PM -0700, Simon Glass wrote:
>> > > > > On Wed, Jan 17, 2018 at 03:07:58PM -0700, Simon Glass wrote:
>> > > > >> On 16 January 2018 at 01:16, Maxime Ripard
>> > > > >> <maxime.ripard at free-electrons.com> wrote:
>> > > > >> > Allow boards and architectures to override the default environment lookup
>> > > > >> > code by overriding env_get_location.
>> > > > >> >
>> > > > >> > Reviewed-by: Andre Przywara <andre.przywara at arm.com>
>> > > > >> > Reviewed-by: Lukasz Majewski <lukma at denx.de>
>> > > > >> > Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
>> > > > >> > ---
>> > > > >> >  env/env.c | 20 +++++++++++++++++++-
>> > > > >> >  1 file changed, 19 insertions(+), 1 deletion(-)
>> > > > >> >
>> > > > >>
>> > > > >> I still don't really understand why this needs to be a weak function.
>> > > > >> If the board knows the priority order, can it not put it into
>> > > > >> global_data? We could have a little u8 array of 4 items with a
>> > > > >> terminator?
>> > > > >
>> > > > > Sure that would be simpler, but that would also prevent us from doing
>> > > > > "smart" things based on data other than just whether the previous
>> > > > > environment is usable. Things based for example on a GPIO state, or a
>> > > > > custom algorithm to transition (or duplicate) the environment.
>> > > >
>> > > > In that case the board could read the GPIO state, or the algorithm,
>> > > > and then set up the value.
>> > > >
>> > > > Basically I am saying it could set up the priority order in advance of
>> > > > it being needed, rather than having a callback.
>> > >
>> > > Aren't we kind of stuck here?
>> > >
>> > > On the previous iterations, we already discussed this and Tom
>> > > eventually told he was in favour of __weak functions, and the
>> > > discussion stopped there. I assumed you were ok with it.
>> > >
>> > > I'd really want to move forward on that. This is something that is
>> > > really biting us *now* and I'd hate to miss yet another merge window
>> > > because of debates like this.
>> >
>> > Yes, I think this is where we want things to be weak, with a reasonable
>> > default.  If we start to see that "everyone" does the same thing by and
>> > large we can re-evaluate.
>>
>> Ok.
>>
>> I've fixed the bug I mentionned the other day on IRC, should I send a PR?
>
> Lets give Simon a chance to provide any other feedback here, or another
> argument to convince me that no, we don't want to have this abstracted
> by a weak function but instead ..., thanks!

I suspect there is a reason why this is better than what I propose.
Perhaps when I try it out it will become apparent.

So let's go ahead and revisit later if we have new information.

Reviewed-by: Simon Glass <sjg at chromium.org>

Regards,
Simon